System of steam-heating.



J. A. SERRELL.

SYSTEM OF STEAM HEATING;

APPLICATION FILED JAN. 7, 1910.

1,15%,5QU, PatentedSept. 7, 1915.

2 SHEETSSHEET l- J. A. SERRELL.

SYSTEM OF STEAM HEATING.

APPLICATION FILED JAN. 7. 1910.

2 SHEETS-SHEET Z.

WITNESSES JOHN A. SERRELL, OF N ORTH PLAINFIELD, NEW JERSEY.

SYSTEM OF STEAM-HEATING.

Specification of Letters Patent.

Patented Sept. '7, 1915.

Application filed January 7, 1910. Serial No. 536,894.

To all whom it may concern I 7 Be it known that I, JoHN A. SERRELL, a citizen of the United States, and a resident of North Plainfield, county of Somerset, and State of New Jersey, have invented an Improvement in Systems of Steam-Heating, of which the following is a specification.

My invention has reference to systems of steam heating and consists of certain improvements which are fully set forth in the following specification and shown in the accompanying drawings which form a partthereof.

The object of my invention is to provide a system of steam circulation in which there shall be maintained automatically a constant predetermined difference in pressure between the supply and return sides of the system with respect to the radiators, whereby a proper circulation of steam is insured and the radiators will be efliciently operated as heaters.

My invention depends upon the following requirements, namely; the provision of means by which the difference in pressure in the boiler and the main return will not become great enough to force the water out of the boiler into the return system beyond what would be considered a good working.

condition; provision for causing the condensation from the heating system to flow continuously into the higher pressure in the boiler with assistance of a permissible water column in the return line; provision for insuring a pressure in the return system above the atmospheric pressure to force out the air [while preventing the escape of steam from the system; and provision of means for preventing any flow of air into the return system when the pressure therein is less than that of the atmosphere.

My invention consists of means embodying in the construction and operation the characteristic features above specified, and which means are fully described hereinafter and more specifically pointed out in the claims: and these improvements will be better understood by reference to the drawings, in which:

Figure 1 is a diagrammatic illustrationpf a steam heating system embodying my 1nvention, with part of the apparatus 1n section; Fig. 2 is an enlargedview of a portion of the apparatus shown in Fig. 1; Fig. 3 is a diagrammatic illustration of a steam heating system embodying my improvements with some modifications and Fig. 4 is a secii onalg view of the reducing valve shown in 2 are the radiators of which there may be any number, 3 is the steam supply pipe leading from the boiler 5 in the basement, and 4 is the return pipe for delivering the water of condensation, and preferably the air, into a receiver 8 in'the basement and from which the water passes by gravity through a pipe 9 to the lower part of the boiler 5. The steam is supplied to the radiators from this supply pipe 3 through suitable control valves 6 and by which the amount of steam delivered to the radiators may be regulated.

7 represent automatic return valves or traps and are designed for permitting the free passageofwater and air from the radiators, but restricting the escape of steam. These automatic valves 7 may be of any suitable construction, being such for example as are in general use on vacuum or other systems of steam heating. The receiver 8 receives the water of condensation from the return pipe L and at the water level the said receiver is preferably of large area so as to receive considerable water "without varying the level of the surface therein beyond a moderate amount. Assuming that the level shown in Fig. l in the receiver 8 is the normal level, it will-be seen that this a level is above the normal level in the boiler a distance indicated by a: and this equals the column of water which is supported in the receiver by the superior pressure in the boiler 5' and the supply pipe 3 over that which exists in the return pipe 4: and the receiverS. Whenever the water in the receiver rises above the level indicated, it would automatically overcome the pressure of the boiler and the water would flow through the pipe 9 into the boiler until the proper normal level was again restored.

10 is a steam pipe leading from the supply pipe or, in any other manner, leading from the boiler 5, and said pipe 10 is provided on its end with a valve 11 within the receiver 8 for admitting steam into the receiver whenever the pressure in the boiler becomes abnormally high relative to the pressure in the receiver. This valve 11 is'automatioally operated by a float 17, whose action is dependent upon the level of the water Within the receiver. The air which is received in the receiver 8 is permitted to be blown out through an automatic valve 15, which is also operated by the float 17. The air which passes through the valve-.15 escapes by a pipe 15 out of the receiver; thence passes through a check valve 18 and by a discharge pipe 19 through a Water seal 20 to the escape pipe 21 leading to the atmosphere. The pipe 21 also acts as an overflow for the water seal 20. In case there is no lid used to the water seal, as shown in Fig. 3, then the air will not be required to pass through the pipe 21, and said pipe will merely act as an overflow pipe. The pipe 19 has a considerable drop so as to act as a resistance to the entrance of air, and in case of a vacuum with-- in the receiver 8, to avoid driving the water out of the seal 20 into the receiver. If the check valve 18 is made sufficiently air tight 'to prevent the passage of air, then the water seal 20 may be omitted. Likewise, it is evident that if desired the water seal may be relied upon without the use of the check valve. The valves 11 and 15 are connected so as to be successively operated by the float 17, and these connections will be better understood by reference to Fi 2. The valve piece of valve 11 is operated by a lever 12, and the valve piece of the air relief valve 15 is operated by a lever 14. Thefree ends of the levers 12 and 11 are connected by a link 13 which is jointed at or near'its middle to the upper end of the rod 16 which is secured at its bottom to the float 17. Assuming that in Fig. 2 there is the normal static head desired and with valve 15 open and valve 11 closed, it will be understood that, should the water level rise farther in the receiver 8, it will be because there is an abnormally higher pressure in the boiler, making the distance between the actual level in the receiver 8 and the normal level in the boiler 5 greater than it should be. When the float then rises, it is with the object of increasing the pressure in the receiver and the return line 4, to reduce this diflerentiai in pressure so that it will. equal the predetermined dill'erence corresponding to the column. a of water. As the float rises, the first action to oscillate the link 13 about the end of the lever 1:2- with the result that the valve 15 is closed to shut off the escape to the atmosphere. This action takes place because the lever 12 is weighted at 2%, and consequently does not lift until the lever 14 comes to a stop when the valve is closed. When the valve 15 is closed, the further rising of the float 17 causes the link 13 tolift the free end of thelever 12, and to open the steam valve 11 for the purpose of admitting steam from the boiler into the receiver 8 to increase the pressure in said receiver. In this way the normal difference in pressures between the supply and return sides of the system is maintained irrespective of the variations in pressure in the boiler and the supply pipe. When the steam is discharged through the valve 11 into the receiver, it may be delivered from a nozzle 23 opening through a surrounding port 22 into which the returns i discharge and in this way constitute an ejector which assists in discharging the water of condensation and air from the return pipe into the receiver. This refinement of the apparatus may be omitted, if desired.

As soon as the pressure in the receiver 8 reaches a proper pressure relatively to the pressure in the boiler and supply mains which will insure the maintenance of the predetermined permissible column or static head :12, the valves 11 and 15 are again operated. but in the reverse order. The steam is in this manner shut off from the receiver and then the air valve 15 is opened to allow the escape of the air. the same passing upward through pipe 15, and thence through the check valve 18 and finally through the water seal 20. These devices operate automatically to maintain a pressure above the atmosph re within the system and a differential pressure within the supply and return pipes which may equal a pressure up to that of the permissible static head. When operating at or below atmospheric pressure and until there is a greater difference in pressure between the supply and return than the permissible static head, the valve 15 will be open and the valve 11 shut. In this position of the valves the air will vent itself through the check valve and water seal whenever the pressure in the return is greater than atmospheric pressure plus the resistance of the check and water seal. When the pressure in the boiler rises above that in the receiver or separating tank sufliciently to force the water back into the said receiver to the limit of the permissible static head, it acts on the float 17, first closing the air vent valve 15, and if the accumulated pressure in the receiver is not sufi icient to hold or decrease the water level line and the water still continues to rise, the float will open the valve 11 and admit steam to the receiver in suiflcient quantity. which. in connection with the permissible static head :12, balances the pressure in the boiler.

By the principles involved in my improved apparatus, 1 am enabled to establish a maximum diflerential between the steam supply and the condensation return of a heating system by merely shutting the air -vent and then admitting pressure from the boiler above the pressure of the static column or permissible head, or in case a thermostatic valve 15" was used in place of the valve 15 as the means for permitting the escape of air (see Fig. 3 then by the automatic control of the steam inlet alone under the influence of the float. In this latter case the air and gases would. be continuously maaaeo vented when running under pressure above that of the static head and consequently, the control would be somewhat more uniform if the float were alone required to operate the steam admission. It will be understood, therefore, that I do not restrict myself to the valve mechanism and means of operating the same herein described.

Referring now to Fig. 3, which shows the apparatus somewhat modified but operating on substantially the same principles and accomplishing the same results as those described with reference to Figs. 1 and 2: In Fig. 3 the radiators, supply and return pipes, boiler and valves 6 and 7 are the same as in Fig. 1. In this case, in place of the receiver 8 of Fig. 1, a smaller receiver 8 is employed, which receives the water of condensation from the return pipe 4 and delivers the water of condensation to the boiler by a pipe 9. The normal level in the receiver 8 is above the normal level of the water in the boiler equal to a static head indicated by a as in the case of Fig.1. The air from the receiver 8 is shown as vented through a check valve 18, a thermostatic valve 15, and a water seal 20 into which the air pipe 19 dips, and said water seal may be provided with an overflow 21 as in the case of Fig. 1. In place of a float and valve 11 operated thereby for controlling the supply of steam from the boiler and supply pipe to the receiver and return pipe of the system, as illustrated in Fig. 1, I may employ an ordinary reducing valve of any suitable construction, as indicated at 11*, said valve being arranged in the pipe 10 and preferably outside of the receiver 8. A suitable construction of reducing valve is shown in Fig. 4 in which the steam passing through the pipe 10 is controlled by a balanced valve 26 which is controlled by a diaphragm 27 actuated by steam pressure in the chamber 28 which is in communication with the pipe leading from the boiler, and said pressure counterbalanced by a counterbalance lever 29 having weights 30 and steam pressure above the diaphragm from the receiver side. By adjusting the weights, the pressure reduc ing valve may be caused to open. whenever the pressure in the pipe 10 leading from the boiler contains an excessive pressure above that predetermined by the adjustment ofthe weight 30 and pressurein the receiver. This reducing valve may be adjusted so as to maintain a certain differential in pressure between the pressure in the pipe 10 and in the receiver 8, so that should the pressure in the boiler rise, a correspondingly increased pressure will be admitted to the receiver i to counterbalance what would otherwise be an abnormal static head, and thereby maintain the permissible static head a: unchanged and the radiators to be operated under a predetermined differential in pressure between the supply and return pipes of the system. In the construction shown in Fig. 3 the apparatus will operate, perhaps'more uniformly than in the apparatus shown in Fig. 1, because the reducing valve 11 automatically operates under the influence of the increasing pressure of the boiler and without the necessity of the level of the Water in the reservoir changing to induce the regulation.

In the operation of this system, when the steam pressure generated in the boiler rises above that of the atmosphere it would force the air out of the supply. pipes, radiators and return line, thence through the check valve, thermostatic valve and water seal to sufficient quantity to increase the pressure in the receiver and return pipes, to such an extent as to hold the water line in the receiver 8 below the line of the air vent. When steam reaches the thermostatic valve it will close and so remain closed until either an accumulation of air occurs, or the pressure in the main return drops below the pressure of the atmosphere. In this latter case, the check valve 18 and the water seal 20 will prevent passage of air into'the sys tem. While I have shown the water pan or seal 20 close to the thermostatic valve 15 it is to be understood that it may be placed as low down as desired so as to get any length of pipe 19 required to act as a water column in case a material vacuum were produced in the system. If this column 19 could be made sufficiently long, the check valve 18 might be dispensed with, or if the check valve were sufficiently tight, the barometric column 19 and water seal 20 might be dispensed with. In general, the apparatus on the air vent of the system other than the thermostatic member are mere refinements, and need not be considered. as essential. A safety valve 5 may be employed on the steam main leading from the boiler to relieve an abnormal pressure should it occur from any derangement of the apparatus.

A heating system arranged as shown would circulate and return its condensation to the boiler with aforce equal to the permissible static head a; whether the boiler pressure were considerably higher than atmospheric pressure or below atmospheric pressure, provided there were no leaks and pressure above atmosphere be first generated to force out the air.

The advantage in my improved system lies in the economy of being able to store up the steam caused by fluctuations in the firing of the boiler and in being able to carry a pressure proportional to the outside temperature rather than being limited to a pressure so near atmospheric pressure that there will be no danger of blocking returns and causing Water hammer, or what may be considered a worse evil, forcing the boiler water out through the vent pipe.

I have shown my improvements in forms which are suitable for commercial use, and while I prefer the constructions shown, I do not restrict myself thereto, as the details thereof may be modified in various ways Without departing from the spirit of the invention.

' In this application I make no claim to the method herein described as the same is reserved for a separate application.

Having noW described my invention what I claim as new and desire to secure by Letters Patent, is:

1. In a steam heating system, the combination of the radiators or coils, a steam boiler, a supply pipe from the boiler to the radiators or coils, a return pipe from the radiators or. coils to the boiler and containing a fixed non-condensing receiver at a higher level than the normal Water level of the boiler and in which a static head is maintained, a valve for admitting steam to the receiver whenever the static head therein becomes greater than the predetermined normal static head, motor mechanism for automatically operating the valve and actuated under the influence of the boiler pressure, and-means independent of the motor mechanism for permitting the escape of air from the receiver while restricting the escape of steam at all times during the normal operation of the system.

2. In a steam heating system, the combination of the radiators or coils, a steam boiler, a supply pipe from the boiler to the radiators or coils, a return pipe from the radiators or coils to the boiler and containing near its lower part a fixed receiver arranged at a higher level than the normal water level of the boiler and in which a static head is maintained, automatic trap devices arranged between the radiators or coils and the return pipe for permitting the passage of water and air from the radiators or coils into the return pipe while preventing the passage of steam whereby no appreciable steam is permitted to enter the return pipe and receiver by Way of the radiators, a valve for admitting steam to the receiver Whenever the static head therein becomes greater than that predetermined as the normal static head, motor mechanism for automatically operating the valve and actuated under the influence of the boiler at all times during the normal operation of the system.

3. In a steam heating system, the combination of the radiators or coils, a steam boiler, a supply pipe from the boiler to the' radiators or coils, a return pipe from the radiators for delivering water of condensation to the boiler and air from the radiators, said return pipe containing a fixed receiver at a higher level than the normal water level of the boiler and in which a static head is maintained, automatic means for permitting the escape of water of condensation and air from the radiators or coils into the return pipe while restricting the escape of steam, means for permitting the discharge of air from the return side of the system into the atmosphere While restricting the escape of steam, and separate automatic means controlled by the difference in relative pressures in the boiler and in the return side of the system for admitting steam to the receiver when the static head therein becomes greater than that predetermined as the normal static head.

4. In a steam heating system, the combination of the radiators or coils, a steam boiler, a supply pipe from the boiler to the radiators or coils, a return pipe from the radiators for delivering water of condensation to the boiler said return pipe containing a fixed receiver at a higher level than the normal Water level of the boiler and in which a static head is maintained, thermostatic means for permitting the discharge of air from the receiver into the atmosphere while preventing the escape of steam therefrom, and separate automatic means in addition to the receiver controlled by the difference in relative pressures in the boiler and the return side of the system for admitting steam to the receiver whenever the static head therein becomes greater than that predetermined as the normal static head.

5. In a steam heating system, the combination of the radiators or coils, a steam boiler, a supply pipe from the boiler to the radiators or coils, a return pipe from the radiators to the boiler and containing a receiver at a higher level than the normal water level of the boiler and in which a static head is maintained, automatic traps between the radiators or coils and the return pipe for permitting the passage of air and water but restricting the passage of steam, automatic means influenced by the pressures in the return part of the system for admitting steam tothe receiver Whenever the static head therein becomes greater than that predetermined as the normal static head, said means consisting of a steam pipe receiving steam from the boiler and a pressure reducing valve in the steam pipe adapted to open Wider With any abnormal decrease of pressure in the receiver and vice versa', and automatic means for permitting the escape of air from the return pipe While restricting the escape of steam.

6. In a steam heating system, the combination of the radiators or coils, a steam boiler, a supply pipe from the boiler to the radiators or coils, a return pipe from the radiators or coils to the boiler and containing a fixed receiver at a higher level than the normal Water level of the boiler into which all of the Water of condensation is received and in which a static head is main tained, means independent of the varying pressure in the receiver for automatically discharging air directly from the receiver to the atmosphere and preventing the admission of air from the atmosphere into the receiver, and means for increasing the pressure in the receiver to assist the static head Whenever the said static head and the boiler pressure becomes abnormally high, said means consisting of a valve for admitting steam to the receiver, and motor devices controlled by the relative pressures in the sup ply and return sides of the system for operating the valve.

7. In a steam heating system, the combination of radiators or coils, a steam boiler,

a supply pipe from the boiler to the radiators or coils, a return pipe from the radiators or coils to the boiler and in Which a static head is provided for returning the Water to the boiler, automatic means for admitting steam from the supply side of the system to the return pipe under the control of the pressures in the supply and return sides of the system, and means for permitting the escape of air from the return pipe While restricting the escape of steam.

In testimony of which invention, I hereunto set my hand.

JOHN A. SERRELL.

Witnesses:

WM. M. TREADWELL, CHARLES J. Korr. 

